/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Simon Goldschmidt
 *
 */

/**
 * @file
 * Common functions used throughout the stack.
 *
 */

#include "lwip/opt.h"
#include "lwip/def.h"

#include <string.h>

#if BYTE_ORDER == LITTLE_ENDIAN

#if !defined(lwip_htons)
/**
 * Convert an u16_t from host- to network byte order.
 *
 * @param n u16_t in host byte order
 * @return n in network byte order
 */
u16_t lwip_htons(u16_t n)
{
	return (u16_t) PP_HTONS(n);
}
#endif							/* lwip_htons */

#if !defined(lwip_htonl)
/**
 * Convert an u32_t from host- to network byte order.
 *
 * @param n u32_t in host byte order
 * @return n in network byte order
 */
u32_t lwip_htonl(u32_t n)
{
	return (u32_t) PP_HTONL(n);
}
#endif							/* lwip_htonl */

#endif							/* BYTE_ORDER == LITTLE_ENDIAN */

#ifndef lwip_strnstr
/**
 * lwIP default implementation for strnstr() non-standard function.
 * This can be \#defined to strnstr() depending on your platform port.
 */
char *lwip_strnstr(const char *buffer, const char *token, size_t n)
{
	const char *p;
	size_t tokenlen = strlen(token);
	if (tokenlen == 0) {
		return LWIP_CONST_CAST(char *, buffer);
	}
	for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) {
		if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) {
			return LWIP_CONST_CAST(char *, p);
		}
	}
	return NULL;
}
#endif

#ifndef lwip_stricmp
/**
 * @ingroup sys_nonstandard
 * lwIP default implementation for stricmp() non-standard function.
 * This can be \#defined to stricmp() depending on your platform port.
 */
int lwip_stricmp(const char *str1, const char *str2)
{
	char c1, c2;

	do {
		c1 = *str1++;
		c2 = *str2++;
		if (c1 != c2) {
			char c1_upc = c1 | 0x20;
			if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
				/* characters are not equal an one is in the alphabet range:
				   downcase both chars and check again */
				char c2_upc = c2 | 0x20;
				if (c1_upc != c2_upc) {
					/* still not equal */
					/* don't care for < or > */
					return 1;
				}
			} else {
				/* characters are not equal but none is in the alphabet range */
				return 1;
			}
		}
	} while (c1 != 0);
	return 0;
}
#endif

#ifndef lwip_strnicmp
/**
 * lwIP default implementation for strnicmp() non-standard function.
 * This can be \#defined to strnicmp() depending on your platform port.
 */
int lwip_strnicmp(const char *str1, const char *str2, size_t len)
{
	char c1, c2;

	do {
		c1 = *str1++;
		c2 = *str2++;
		if (c1 != c2) {
			char c1_upc = c1 | 0x20;
			if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
				/* characters are not equal an one is in the alphabet range:
				   downcase both chars and check again */
				char c2_upc = c2 | 0x20;
				if (c1_upc != c2_upc) {
					/* still not equal */
					/* don't care for < or > */
					return 1;
				}
			} else {
				/* characters are not equal but none is in the alphabet range */
				return 1;
			}
		}
	} while (len-- && c1 != 0);
	return 0;
}
#endif

#ifndef lwip_itoa
/**
 * lwIP default implementation for itoa() non-standard function.
 * This can be \#defined to itoa() or snprintf(result, bufsize, "%d", number) depending on your platform port.
 */
void lwip_itoa(char *result, size_t bufsize, int number)
{
	const int base = 10;
	char *ptr = result, *ptr1 = result, tmp_char;
	int tmp_value;
	LWIP_UNUSED_ARG(bufsize);

	do {
		tmp_value = number;
		number /= base;
		*ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 + (tmp_value - number * base)];
	} while (number);

	/* Apply negative sign */
	if (tmp_value < 0) {
		*ptr++ = '-';
	}
	*ptr-- = '\0';
	while (ptr1 < ptr) {
		tmp_char = *ptr;
		*ptr-- = *ptr1;
		*ptr1++ = tmp_char;
	}
}
#endif
